Effectiveness of budesonide-succinate-dextran conjugate as a novel prodrug of budesonide against acetic acid-induced colitis in rats

Effects of the anti-inflammatory drug budesonide on the gut microbiota and cytokine production of 13-lined ground squirrels during prehibernation fattening

The gut microbiome is essential for maintaining organismal health. Gut microbiota may be disrupted through external factors like dietary change, which can lead to gut inflammation, resulting in obesity. Hibernating mammals develop low-grade gut inflammation when they accumulate fat deposits in preparation for hibernation, making them useful models for studying the relationship between the microbiome, inflammation, and weight gain. Nonsteroidal anti-inflammatory drugs and steroids are commonly used in humans to target gut inflammation, but how these drugs affect the gut microbiome and its stability is unclear. We investigated the effect of the glucocorticoid drug budesonide on the gut microbiome and cytokine levels of an obligate hibernator, the 13-lined ground squirrel, during the fattening season. We used 16S rRNA gene sequencing to characterize bacterial communities in the lumen and mucosa of the cecum and colon and measured proinflammatory [tumor necrosis factor-α (TNF-α)/interleukin 6 (IL-6)] and anti-inflammatory (IL-10) cytokine levels. Budesonide affected the microbiome only in the cecum lumen, where bacterial diversity was higher in the control group, and communities significantly differed between treatments. Across gut sections, Marvinbryantia and Enterococcus were significantly higher in the budesonide group, whereas Sarcina was higher in the control group. TNF-α and IL-6 levels were higher in control squirrels compared with the budesonide group, but there was no difference in IL-10 levels. Overall, budesonide treatment affected the microbial community and diversity of 13-lined ground squirrels in the cecum lumen. Our study presents another step toward developing ground squirrels as a model for studying the interaction between the microbiota and host inflammation.NEW & NOTEWORTHY Disruptions of gut microbiota can lead to inflammation, resulting in weight gain. Inflammation can be treated with budesonide, but how budesonide affects gut microbiota is unclear. Thirteen-lined ground squirrels experience low-grade gut inflammation during prehibernation fattening, which compares with human inflammation-weight gain mechanisms. We showed that budesonide treatment decreased microbiome diversity and lead to a shift in community in the cecum lumen. Our study supports developing ground squirrels as a model for studying microbiome-inflammation interactions.

pH-sensitive HPMCP-chitosan nanoparticles containing 5-aminosalicylic acid and berberine for oral colon delivery in a rat model of ulcerative colitis

Ulcerative colitis (UC) with continuous and extensive inflammation is limited to the colon mucosa and can lead to abdominal pain, diarrhea, and rectal bleeding. Conventional therapies are associated with several limitations, such as systemic side effects, drug degradation, inactivation, and limited drug uptake, leading to poor bioavailability. These restrictions necessitate drug delivery to the colon so that the drug passes through the stomach unchanged and has selective access to the colon. The present study aimed to formulate 5-aminosalicylic acid (5-ASA) and berberine (BBR) in chitosan nanoparticles cross-linked by HPMCP (hydroxypropyl methylcellulose phthalate) as a colon drug delivery system for UC. Spherical nanoparticles were prepared. They showed appropriate drug release in the simulated intestinal fluid (SIF), while the release did not occur in the simulated gastric fluid (SGF). They improved disease activity parameters (DAI) and ulcer index, increased the length of the colon, and decreased the wet weight of the colon. Furthermore, histopathological colon studies showed an improved therapeutic effect of 5-ASA/HPMCP/CSNPs and BBR/HPMCP/CSNPs. In conclusion, although 5-ASA/HPMCP/CSNPs showed the best effect in the treatment of UC, BBR/HPMCP/CSNPs, and 5-ASA/BBR/HPMCP/CSNPs were also effective in vivo study, and this study anticipated they could be helpful in future clinical applications for the management of UC.

Amelioration of Colitis by a Gut Bacterial Consortium Producing Anti-Inflammatory Secondary Bile Acids

The Integrative Human Microbiome Project and other cohort studies have indicated that inflammatory bowel disease is accompanied by dysbiosis of gut microbiota, decreased production of secondary bile acids, and increased levels of primary bile acids. Secondary bile acids, such as ursodeoxycholic acid (UDCA) and lithocholic acid (LCA), have been reported to be anti-inflammatory, yet it remains to be studied whether introducing selected bacteria strains to restore bile acid metabolism of the gut microbiome can alleviate intestinal inflammation. In this study, we screened human gut bacterial strains for bile acid metabolism and designed a consortium of three species, including Clostridium AP sp000509125, Bacteroides ovatus, and Eubacterium limosum, and named it BAC (bile acid consortium). We showed that the three-strain gut bacterial consortium BAC is capable of converting conjugated primary bile acids taurochenodeoxycholic acid and glycochenodeoxycholic acid to secondary bile acids UDCA and LCA in vitro. Oral gavage treatment with BAC in mice resulted in protective effects against dextran sulfate sodium (DSS)-induced colitis, including reduced weight loss and increased colon length. Furthermore, BAC treatment increased the fecal level of bile acids, including UDCA and LCA. BAC treatment enhanced intestinal barrier function, which may be attributed to the increased activation of the bile acid receptor TGR5 by secondary bile acids. Finally, we examined the remodeling of gut microbiota by BAC treatment. Taken together, the three-strain gut bacterial consortium BAC restored the dysregulated bile acid metabolism and alleviated DSS-induced colitis. Our study provides a proof-of-concept demonstration that a rationally designed bacterial consortium can reshape the metabolism of the gut microbiome to treat diseases. IMPORTANCE Secondary bile acids have been reported to be anti-inflammatory, yet it remains to be studied whether introducing selected bacteria strains to restore bile acid metabolism of the gut microbiome can alleviate intestinal inflammation. To address this gap, we designed a consortium of human gut bacterial strains based on their metabolic capacity to produce secondary bile acids UDCA and LCA, and we evaluated the efficacy of single bacterial strains and the bacterial consortium in treating the murine colitis model. We found that oral gavage of the bacterial consortium to mice restored secondary bile acid metabolism to increase levels of UDCA and LCA, which induced the activation of TGR5 to improve gut-barrier integrity and reduced the inflammation in murine colitis. Overall, our study demonstrates that rationally designed bacterial consortia can reshape the metabolism of the gut microbiome and provides novel insights into the application of live biotherapeutics for treating IBD.

Preparation and Characterization of a Novel Multiparticulate Dosage Form Carrying Budesonide-Loaded Chitosan Nanoparticles to Enhance the Efficiency of Pellets in the Colon

An attempt was made to conquer the limitation of orally administered nanoparticles for the delivery of budesonide to the colon. The ionic gelation technique was used to load budesonide on chitosan nanoparticles. The nanoparticles were investigated in terms of size, zeta potential, encapsulation efficiency, shape and drug release. Then, nanoparticles were pelletized using the extrusion-spheronization method and were investigated for their size, mechanical properties, and drug release. Pellets were subsequently coated with a polymeric solution composed of two enteric (eudragit L and S) and time-dependent polymers (eudragit RS) for colon-specific delivery. All formulations were examined for their anti-inflammatory effect in rats with induced colitis and the relapse of the colitis after discontinuation of treatment was also followed. The size of nanoparticles ranged between 288 ± 7.5 and 566 ± 7.7 nm and zeta potential verified their positive charged surface. The drug release from nanoparticles showed an initial burst release followed by a continuous release. Pelletized nanoparticles showed proper mechanical properties and faster drug release in acidic pH compared with alkaline pH. It was interesting to note that pelletized budesonide nanoparticles released the drug throughout the GIT in a sustained fashion, and had long-lasting anti-inflammatory effects while rapid relapse was observed for those treated with conventional budesonide pellets. It seems that there is a synergistic effect of nanoformulation of budesonide and the encapsulation of pelletized nanoparticles in a proper coating system for colon delivery that could result in a significant and long-lasting anti-inflammatory effect.

Functional Plasmon-Activated Water Increases Akkermansia muciniphila Abundance in Gut Microbiota to Ameliorate Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is associated with dysbiosis and intestinal barrier dysfunction, as indicated by epithelial hyperpermeability and high levels of mucosal-associated bacteria. Changes in gut microbiota may be correlated with IBD pathogenesis. Additionally, microbe-based treatments could mitigate clinical IBD symptoms. Plasmon-activated water (PAW) is known to have an anti-inflammatory potential. In this work, we studied the association between the anti-inflammatory ability of PAW and intestinal microbes, thereby improving IBD treatment. We examined the PAW-induced changes in the colonic immune activity and microbiota of mice by immunohistochemistry and next generation sequencing, determined whether drinking PAW can mitigate IBD induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS) and dysbiosis through mice animal models. The effects of specific probiotic species on mice with TNBS-induced IBD were also investigated. Experimental results indicated that PAW could change the local inflammation in the intestinal microenvironment. Moreover, the abundance of Akkermansia spp. was degraded in the TNBS-treated mice but elevated in the PAW-drinking mice. Daily rectal injection of Akkermansia muciniphila, a potential probiotic species in Akkermansia spp., also improved the health of the mice. Correspondingly, both PAW consumption and increasing the intestinal abundance of Akkermansia muciniphila can mitigate IBD in mice. These findings indicate that increasing the abundance of Akkermansia muciniphila in the gut through PAW consumption or other methods may mitigate IBD in mice with clinically significant IBD.

Advances in the treatment of inflammatory bowel disease: Focus on polysaccharide nanoparticulate drug delivery systems

The complex pathogenesis of inflammatory bowel disease (IBD) explains the several hurdles for finding an efficient approach to cure it. Nowadays, therapeutic protocols aim to reduce inflammation during the hot phase or maintain remission during the cold phase. Nonetheless, these drugs suffer from severe side effects or poor efficacy due to low bioavailability in the inflamed region of the intestinal tract. New protocols based on antibodies that target proinflammatory cytokines are clinically relevant. However, besides being expensive, their use is associated with a primary nonresponse or a loss of response following a long administration period. Accordingly, many researchers exploited the physiological changes of the mucosal barrier for designing nanoparticulate drug delivery systems to target inflamed tissues. Others exploited biocompatibility and relative affordability of polysaccharides to test their intrinsic anti-inflammatory and healing properties in IBD models. This critical review updates state of the art on advances in IBD treatment. Data on using polysaccharide nanoparticulate drug delivery systems for IBD treatment are reviewed and discussed.

Validation of a HPLC-UV method for the quantification of budesonide in skin layers

A simple and sensitive HPLC method for the quantification of budesonide in skin layers was developed and validated. Budesonide was extracted from stratum corneum, epidermis and dermis by means of a mixture of acetonitrile:water (recovery > 90%). Budesonide quantification was performed with a RP-C18 column using methanol and water mixture (69:31, v/v) as mobile phase, pumped at 0.8 ml/min. The absorbance was monitored at 254 nm. The method resulted to be selective, linear in the range 0.05-5 or 10 μg/ml, precise and accurate. LLOQ resulted to be 0.05 μg/ml. The developed method appeared to be appropriate for the quantification of budesonide in skin layers at the end of in vitro permeation experiments since the recovery of the applied dose was 97 ± 1%, in line with requirement of the OECD guideline for the testing of the chemicals (Skin absorption: in vitro method).

Nanogels of Succinylated Glycol Chitosan-Succinyl Prednisolone Conjugate: Preparation, In Vitro Characteristics and Therapeutic Potential

A novel anionic nanogel system was prepared using succinylated glycol chitosan-succinyl prednisolone conjugate (S-GCh-SP). The nanogel, named NG(S), was evaluated in vitro and in vivo. S-GCh-SP formed a nanogel via the aggregation of hydrophobic prednisolone (PD) moieties and the introduced succinyl groups contributed to the negative surface charge of the nanogel. The resultant NG(S) had a PD content of 13.7% (w/w), was ca. 400 nm in size and had a ζ-potential of −28 mV. NG(S) released PD very slowly at gastric pH and faster but gradually at small intestinal pH. Although NG(S) was easily taken up by the macrophage-like cell line Raw 264.7, it did not decrease cell viability, suggesting that the toxicity of the nanogel was very low. The in vivo evaluation was performed using rats with trinitrobenzene sulfonic acid (TNBS)-induced colitis. NG(S) and PD alone were not very effective at 5 mg PD eq./kg. However, NG(S) at 10 mg PD eq./kg markedly suppressed colonic damage, whereas PD alone did not. Furthermore, thymus atrophy was less with NG(S) than with PD alone. These results demonstrated that NG(S) is very safe, promotes drug effectiveness and has low toxicity. NG(S) has potential as a drug delivery system for the treatment of ulcerative colitis.

Budesonide-Loaded Eudragit S 100 Nanocapsules for the Treatment of Acetic Acid-Induced Colitis in Animal Model

Nanoparticles for colon-drug delivery were designed and evaluated to solve many discrepancy issues as insufficient drug amount at diseased regions, high adverse effects of released drugs, and unintentionally premature drug release to noninflamed gastrointestinal regions. Herein, the prepared budesonide-loaded Eudragit S 100/Capryol 90 nanocapsules for the treatment of inflammatory bowel disease. Nanocapsules were prepared efficiently by nanoprecipitation technique and composed mainly of the pH-sensitive Eudragit S 100 polymeric coat with a semisynthetic Capryol 90 oily core. Full 3¹ × 2¹ factorial design was applied to obtain optimized nanocapsules. Optimal nanocapsules showed mean particle size of 171 nm with lower polydispersity index indicating the production of monodispersed system and negative zeta-potential of - 37.6 mV. Optimized nanocapsules showed high encapsulation efficiency of 83.4% with lower initial rapid release of 10% for first 2 h and higher rapid cumulative release of 72% after 6 h. The therapeutic activity of the prepared budesonide-loaded nanocapsules was evaluated using a rat colitis model. Disease activity score, macroscopical examination, blood glucose level, and histopathological assessment showed marked improvements over that free drug suspension. Obtained results demonstrate that the budesonide-loaded Eudragit S 100 nanocapsules are an effective colon-targeting nanosystem for the treatment of inflammatory bowel disease. Capryol 90 was found to be a successful, and even preferred, alternative to benzyl benzoate, which is commonly employed as the oil core of such nanocapsules.

Thermoreversible mucoadhesive polymer-drug dispersion for sustained local delivery of budesonide to treat inflammatory disorders of the GI tract

Mucoadhesive drug formulations have been studied and used as alternatives to conventional formulations in order to achieve prolonged retention at the intended site. In addition to providing a controlled drug release, several drugs and disease conditions might benefit from mucoadhesive formulations, contributing to better therapeutic outcomes. Here, we describe the development and the in vitro/in vivo characterization of a mucoadhesive in situ gellifying formulation using PF127, a thermo reversible polymer, entrapping budesonide (BUD), a potent corticosteroid used for the treatment of a wide range of inflammatory diseases, including those affecting mucosas, such as in the GI tract. PF127 formulations (15-17%) were successfully prepared by a cold method as a thermo reversible in situ gelling dispersion for mucosal drug delivery, as confirmed by DSC. Sol-gel temperatures of PF127 formulations (25-39 °C) were observed by dynamic gelation and determined by microrheology and oscillatory rheometry. X-ray diffractograms and TEM images showed that BUD was completely solubilized within the polymeric micelles. In vitro, the gels showed 5-14 g force of mucoadhesion, and the ex vivo studies confirmed that the formulation efficiently adhered to the mucosa. Histopathological analysis combined with fluorescence images and ex vivo intestinal permeation confirmed that the formulation remained on the TGI mucosa for at least 4 h after administration. In vivo studies conducted in a murine model of intestinal mucositis demonstrated that the 16% PF127 BUD formulation was able to resolve the inflammatory injury in the intestinal mucosa. Results demonstrate that fine-tuning of PF127 formulations along with adequate selection of the drug agent, thorough characterization of the dispersions and their interactions with biological interfaces leads to the development of effective controlled drug delivery systems targeted to GI inflammatory diseases.

Characterization of a dextran-budesonide prodrug for inhalation therapy

Reducing the dosing frequency of corticosteroids may increase compliance and increase pulmonary targeting. The objective of this study was to evaluate whether a high molecular weight dextran-budesonide conjugate might be suitable for pulmonary slow release of the otherwise fast absorbed budesonide. An array of dextran-spacer-budesonide conjugates was prepared that differed in the molecular weight of dextran (20 kDa or 40 kDa) and the length of the dicarboxylic spacer (succinic, glutaric, and adipic anhydride). The conjugates were characterized for identity by proton nuclear magnetic resonance (¹H NMR) and Fourier-transform infrared spectroscopy (FTIR), the degree of dextran-hydroxyl conjugation, purity, and physiological activation (release of budesonide). The 40 kDa dextran-succinate-budesonide conjugate was formulated as a dry powder for pulmonary delivery and characterized for particle size distribution, particle morphology, and aerodynamic particle size. The degree of substitution (grams of budesonide in 100 g of conjugate) ranged from 4 to 10% for all six dextran-spacer-budesonide conjugates. Incubation at 37 °C and pH 7.4 in phosphate buffered saline resulted in release of 25-75% of the conjugated budesonide over an 8-hour period with the rate of release increasing with molecular weight of dextran and the length of the spacer. Modeling of the concentration time profiles of the released budesonide and budesonide-21-hemisucinate in phosphate buffered saline, suggested that budesonide is generated either directly or via the budesonide-21-hemisucinate pre-cursor. Data also suggested that the rate of budesonide generation likely depends on the position of budesonide on the dextran molecule. Spray-drying the 40 kDa dextran-succinate-budesonide produced respirable particles of the conjugate with a mass median aerodynamic particle size (MMAD) of 4 μm. The slow generation of budesonide from the chemical delivery system might further improve the pharmacological profile of budesonide.

Sodium selenite ameliorates both intestinal and extra-intestinal changes in acetic acid-induced colitis in rats

Selenium and its derivatives including sodium selenite (sod sel) belong to the group of essential trace elements needed for proper health and nutrition. They are fairly safe and possess antioxidant and anti-inflammatory properties. The aim of present investigation was to elucidate the effect of sod sel on experimental colitis model in rats. Colitis was induced by intrarectal instillation of 4% (v/v) acetic acid. Two hours later, sod sel was given to rats on a daily basis for 15 consecutive days. Clinical symptoms, colon mass index, spleen weight inflammatory markers, hematological, biochemical, macroscopic, and histological changes were determined. Sod sel markedly ameliorated colitis as evidenced by a significant decrease in macroscopic and microscopic score, disease activity index, colon mass index, and spleen weight. Treatment with sod sel attenuated oxidative stress in the colon by normalizing the colonic content of nitric oxide, malondialdehyde, and reduced glutathione, as well as the activities of catalase, superoxide dismutase, and junctional adhesion molecule (JAM-a). In addition, it significantly reduced colonic myeloperoxidase content, the intercellular adhesion molecule (ICAM-1), and the proinflammatory cytokines; TNF-α, IL-1β. Moreover, sod sel normalized hematological parameters, serum transaminases, and kidney and liver function enzymes. The current study indicates that sod sel was effective in ameliorating the intestinal and extra-intestinal manifestation in acetic acid-induced colitis through its antioxidant, anti-inflammatory, and immunomodulatory effects.

Epiisopiloturine, an imidazole alkaloid, reverses inflammation and lipid peroxidation parameters in the Crohn disease model induced by trinitrobenzenosulfonic acid in Wistar rats

Epiisopiloturine (EPI) is an important imidazole alkaloid because of its pharmacological properties. The aim of this study was to investigate the effects of epiisopiloturine on inflammatory parameters of the colonic mucosa in a rat model of Crohn's disease (CD). For this, we induced colitis using trinitrobenzenosulfonic acid and determined myeloperoxidase (MPO), interleukin 1 β (IL-1β), glutathione (GSH), and malondialdehyde (MDA) levels in the intestinal mucosa. The location and expression of the inflammatory markers in the colon were investigated by immunohistochemistry for NO synthase induced (iNOS), interleukin 1 beta (IL-1β), and cyclooxygenase-2 (COX-2) and western blotting (iNOS and COX-2), respectively. Compared with TNBS alone, epiisopiloturine at 1 mg/kg reduced the macroscopic and microscopic scores, wet weight of the colon, and neutrophilic infiltration and expression of the pro-inflammatory cytokine IL-1β. Epiisopiloturine at 1 mg/kg maintained or restored GSH levels and simultaneously decreased MDA levels. Animals treated with epiisopiloturine exhibited reduced immunostaining for IL-1β, iNOS, and COX-2 and reduced cell count per field. Epiisopiloturine reduced the expression of COX-2 and iNOS in the colon. Based on these findings, we conclude that epiisopiloturine at 1 mg/kg may be an important pharmacological tool against intestinal inflammatory diseases due to its inhibitory action on key enzymes and products involved in inflammation.

Evaluation of central and peripheral effects of doxepin on acetic acid-induced colitis in rat and the involved mechanisms

Anti-colitis effect of antidepressants has been demonstrated recently. Doxepin, a tricyclic antidepressant drug (TCA), with potent H₁, H₂, alpha₁ adrenergic and muscarinic receptor blocking effects could be a good candidate for investigation for its anti-colitis activity. Moreover high prevalence of depression in patients who suffer from IBD (inflammatory bowel disease), defends this idea that adjuvant therapy with an antidepressant drug which has anti-inflammatory effect, may exert favorable effects in the control of the disease. In this study colitis was induced by acetic acid instillation into rat's colon. Doxepin was injected by intraperitoneal (10, 20, 40 mg/kg, twice daily, i.p.) or intracerebroventricular (50 and 100 microgram/rat, i.c.v.) routes to separate the mechanisms are absolutely exerted centrally or mediated both centrally and peripherally prior to induction of colitis. Dexamethasone (2 mg/kg/day, i.p.) was used as reference drug. All the treatments continued for three successive days. The effectiveness of drug was evaluated by determination of cytokines (TNFα, IL6 and IL1β) and myeloperoxidase (MPO) activity as well as macroscopic scores and histopathological parameters. Doxepin after i.p. administration was effective to reduce colitis severity through reduction in the macroscopic and microscopic colonic parameters, MPO activity and cytokines levels. Intracerebroventricular administration of the drug in contrast, did not show any significant protective effect suggesting no important central mechanisms for anti-colitis activity of doxepin. Doxepin as an ancient antidepressive drug has anti-colitis and anti-inflammatory properties which are mainly exerted peripherally so it could be introduced as a good candidate for depressed people who suffered from IBD disorders.

The effect of menthol on acute experimental colitis in rats

Menthol is an aromatic compound with high antiinflammatory activity. The purpose of the current research is to investigate the effectiveness of menthol on acetic acid induced acute colitis in rats. Animals were injected with menthol (20 and 50 and 80mg/kg, i.p.) 24h prior to induction of colitis for 3 consecutive days. Menthol at medium and higher doses similar to dexamethasone as a reference drug significantly reduced body weight loss, macroscopic damage score, ulcer area, colon weight, colon length and improved hematocrit in rats with colitis. The histopathological examination also confirmed anti-colitic effects of menthol. Menthol also reduced significantly the colonic levels of tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), interleukin 6 (IL-6) and myeloperoxidase (MPO) activity in inflamed colons. Thus, the findings of the current study provide evidence that menthol may be beneficial in patients suffering from acute ulcerative colitis.

Coatless alginate pellets as sustained-release drug carrier for inflammatory bowel disease treatment

Conventional alginate pellets underwent rapid drug dissolution and failed to exert colon targeting unless subjected to complex coating. This study designed coatless delayed-release oral colon-specific alginate pellets for ulcerative colitis treatment. Alginate pellets, formulated with water-insoluble ethylcellulose and various calcium salts, were prepared using solvent-free melt pelletization technique which prevented reaction between processing materials during agglomeration and allowed reaction to initiate only in dissolution. Combination of acid-soluble calcium carbonate and highly water-soluble calcium acetate did not impart colon-specific characteristics to pellets due to pore formation in fragmented matrices. Combination of moderately water-soluble calcium phosphate and calcium acetate delayed drug release due to rapid alginate crosslinking by soluble calcium from acetate salt followed by sustaining alginate crosslinking by calcium phosphate. The use of 1:3 ethylcellulose-to-alginate enhanced the sustained drug release attribute. The ethylcellulose was able to maintain the pellet integrity without calcium acetate. Using hydrophobic prednisolone as therapeutic, hydrophilic alginate pellets formulated with hydrophobic ethylcellulose and moderately polar calcium phosphate exhibited colon-specific in vitro drug release and in vivo anti-inflammatory action. Coatless oral colon-specific alginate pellets can be designed through optimal formulation with melt pelletization as the processing technology.

Effects of Malva sylvestris and Its Isolated Polysaccharide on Experimental Ulcerative Colitis in Rats

Malva sylvestris is an edible plant that is consumed as a herbal supplement for its antiulcer and colon cleansing properties in traditional Persian medicine. This study was designed to evaluate its effects on ulcerative colitis, which is a chronic gastrointestinal inflammation. Colitis was induced by rectal instillation of acetic acid solution. Rats in different groups received aqueous, n-hexane, or ethanolic fractions of the plant before induction of colitis. Isolated polysaccharide of plant was also tested in 2 groups before and after induction of colitis. Macroscopic and microscopic evaluation of colitis showed that the aqueous fraction was very effective in preventing the inflammation and efficacy was lower for ethanolic and n-hexane fractions. Polysaccharide was effective in reducing signs of inflammation, especially as pretreatment. These beneficial effects provide evidences that this plant can be suggested for patients with this disease to improve their health condition or to reduce adverse effects of their medication.

Eudragit nanoparticles loaded with silybin: a detailed study of preparation, freeze-drying condition and in vitro/in vivo evaluation

The objective of this work was use of silybin nanoparticles in treatment of ulcerative colitis (UC). Eudragit RL PO nanoparticles loaded with silybin were produced using solvent-evaporation emulsification technique. Then, they were coated by Eudragit FS30D. Drug release was studied in different physiological environments. Colitis was induced by 4% of acetic acid in rats which received freeze-dried nanoparticles of silybin (75 mg/kg/day), dexamethasone (1 mg/kg/day), blank nanoparticles and normal saline orally for 5 days. Then macroscopic, histopathological evaluation and biochemical analysis, including myeloperoxidase (MPO) activity, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels in colon tissues were determined using enzyme-linked immunosorbent assay (ELISA) kits. Macroscopic and histopathological scores were improved by the optimised nanoparticles. The optimised nanoparticles had a particle size of 109 ± 6 nm, zeta potential of 15.4 ± 2 mV, loading efficiency of 98.3 ± 12% and release efficiency of 40.8 ± 5.5% at 24 h. TNF-α, IL-6 and MPO activity were reduced significantly by nanoparticles compared to control group (p < 0.05).

Evaluation of anti-colitic effect of fluvoxamine against acetic acid-induced colitis in normal and reserpinized depressed rats

High prevalence of psychological comorbidities such as depression and anxiety in patients with inflammatory bowel disease (IBD) supports the premise that adding an anti-depressant drug with known anti-inflammatory effect to the medical treatment have beneficial effect in the course of the underlying disease. Colitis was induced by intracolonic instillation of 2 ml of 4% v/v acetic acid solution in rats. Anti-colitic effect of fluvoxamine was evaluated in two categories: A: normal rats, B: reserpinized (6 mg/kg, i.p.) depressed rats. In group A, fluvoxamine (2.5, 5, 10 mg/kg, i.p.) was administered 2 h after induction of colitis and in group B: reserpine (6 mg/kg, i.p.) was administered 1 h prior to colitis induction and then fluvoxamine (2.5, 5, 10 mg/kg, i.p.) was administered 2 h after colitis induction. Dexamethasone (1 mg/kg) was used as reference drug. All the treatments continued daily for five days. The effect was assessed on the basis of macroscopic score, biochemical (myeloperoxidase) changes and histopathological studies. Results showed that fluvoxamine (2.5 and 5 mg/kg) and dexamethasone treatment markedly reduced disease severity in both reserpinized and non-reserpinized rats as indicated by reduction in macroscopic and microscopic colonic damages while reserpine adversely exacerbated the colitis damage. Myeloperoxidase activity which was increased following colitis induction was also decreased. The findings of this study elucidate the anti-colitic and anti-inflammatory properties of fluvoxamine and so introduced it as a good candidate to treat depressive symptoms in people comorbid to IBD.

Beneficial Effects of Maprotiline in a Murine Model of Colitis in Normal and Reserpinised Depressed Rats

Background. Anti-inflammatory and immunomodulatory activities have been reported for maprotiline, a strong norepinephrine reuptake inhibitor. In addition, some other antidepressant drugs have shown beneficial effects in experimental colitis. Methods. All the animals were divided into normal and depressed groups. In normal rats colitis was induced by instillation of 2 mL of 4% acetic acid and after 2 hours, maprotiline (10, 20, and 40 mg/kg, i.p.) was administered. In reserpinised depressed rats, depression was induced by injection of reserpine (6 mg/kg, i.p.), 1 h prior to colitis induction, and then treated with maprotiline (10, 20, and 40 mg/kg). Treatment continued daily for four days. Dexamethasone (1 mg/kg, i.p.) was given as a reference drug. On day five following colitis induction, animals were euthanized and distal colons were assessed macroscopically, histologically, and biochemically (assessment of myeloperoxidase activity). Results. Maprotiline significantly improved macroscopic and histologic scores and diminished myeloperoxidase activity in both normal and depressed rats while reserpine exacerbated the colonic damage. Conclusion. Our data suggests that the salutary effects of maprotiline on acetic acid colitis are probably mediated first through depressive behavioral changes that could be mediated through the brain-gut axis and second for the anti-inflammatory effect of the drug.

Inflammatory cells' role in acetic acid-induced colitis

Background:

Free radicals are the known mechanisms responsible for inducing colitis with two origins: Inflammatory cells and tissues. Only the inflammatory cells can be controlled by corticosteroids. Our aim was to assess the importance of neutrophils as one of the inflammatory cells in inducing colitis and to evaluate the efficacy of corticosteroids in the treatment of inflammatory bowel disease (IBD).

Materials and Methods:

Thirty-six mice were divided into six groups of six mice each. Colitis was induced in three groups by exposing them to acetic acid through enema (group 1), ex vivo (group 3), and enema after immune suppression (group 5). Each group had one control group that was exposed to water injection instead of acetic acid. Tissue samples were evaluated and compared based on macroscopic damages and biochemical and pathological results.

Results:

Considering neutrophilic infiltration, there were significant differences between groups 1, 3, 5, and the control of group 1. Groups 3, 5, and their controls, and group 1 and the control of group 3 had significant differences in terms of goblet depletion. Based on tissue originated H₂O₂, we found significant differences between group 1 and its control and group 3, and also between groups 5 and the control of group 3. All the three groups were significantly different from their controls based on Ferric Reducing Ability of Plasma (FRAP) and such differences were also seen between group 1 with two other groups.

Conclusion:

Neutrophils may not be the only cause of oxidation process in colitis, and also makes the effectiveness of corticosteroids in the treatment of this disease doubtful.

A nitrophenyl-based prodrug type for colorectal targeting of prednisolone, budesonide and celecoxib

Celecoxib is a COX-2 inhibitor drug that can be used to reduce the risk of colorectal adenocarcinoma. Glucocorticoids are used in the treatment of inflammatory bowel disease. A limitation to the use of both drug types is that they undergo absorption from the intestinal tract with serious side effects. The prodrug systems introduced here involve forming a nitro-substituted acylsulfonamide group in the case of celecoxib and a nitro-substituted 21-ester for the glucocorticoids. Drug release is triggered by the nitro reductase action of the colonic microflora, liberating a cyclization competent species. The release of the active parent drugs was evaluated in vitro using Clostridium perfringens and epithelial transport through Caco-2 monolayer evaluation was carried out to estimate the absorption properties of the prodrugs compared to the parental drugs.

Effect of Boswellia serrata on antioxidant status in an experimental model of colitis rats induced by acetic acid

AIM OF THE STUDY

To evaluate the antioxidant effect of an extract of the plant Boswellia serrata in an experimental model of acute ulcerative colitis induced by administration of acetic acid (AA) in rats.

MATERIALS AND METHODS

The extract of B. serrata (34.2 mg/kg/day) was administered orally by gavage for 2 days before and after induction of colitis with AA diluted to 4 % and in a volume of 4 ml.

RESULTS

The anal sphincter pressure in the groups treated with B. serrata showed a significant increase compared to the colitis group (P < 0.001). Histological analysis of treated animals showed less edema with preservation of mucosal crypts. Lipid peroxidation showed a significant decrease in the treated groups compared to the colitis group (P < 0.001). The superoxide dismutase (SOD) enzyme activity showed a significant reduction in the treated groups compared to the colitis group (P < 0.001), the glutathione peroxidase (GPx) significantly increased in the treated groups compared to colitis group (P < 0.05), and the same was the result for enzyme activity glutathione (GSH; P < 0.05).

CONCLUSIONS

The extract of B. serrata has active antioxidant substances that exert protective effects in acute experimental colitis.

Budesonide in the treatment of inflammatory bowel disease

Inflammatory bowel disease, including Crohn's disease and ulcerative colitis, features recurrent episodes of inflammation of the GI tract. The treatment of inflammatory bowel disease is aimed at breaking the cycle of relapsing and remitting inflammation by inducing and maintaining remission. Systemically active conventional corticosteroids have long played a role in the induction of remission in both Crohn's disease and ulcerative colitis, however, their long-term use can lead to adverse systemic effects. Budesonide, a synthetic steroid, has potent local anti-inflammatory effects and limited systemic bioavailability making it an appealing therapeutic option. Ulcerative colitis with predominantly distal disease may be treated with topical budesonide, however, novel oral controlled-release formulations have also been developed to allow for treatment of the entire colon. This article summarizes the use of budesonide in the management of inflammatory bowel disease.

Microencapsulation of budesonide with dextran by spray drying technique for colon-targeted delivery: an in vitro/in vivo evaluation in induced colitis in rat

The aim of this study was developing colon targeted-delivery of budesonide for ulcerative colitis. Microcapsules were prepared using spray drying technique by different drug-to-dextran ratios and three molecular weights (MWs) of polymer. Differential scanning calorimetry, X-ray diffraction (XRD), drug release and loading efficiency of microcapsules were studied. In vivo efficacy of the selected formulation prepared by 1 : 10 drug-to-polymer ratio and dextran with MW 500 000 (D10M500) against acetic acid-induced colitis in rats was evaluated and compared to the control and reference groups (mesalasine and budesonide suspensions). The results showed that D10M500 microcapsules could target the drug to colon and its efficacy in reducing macroscopic damage score was higher than mesalasine suspension. Treatment with D10M500 decreased the scores of crypt damage and total colitis significantly compared to the control group which just received the vehicle and the groups treated with mesalasine and budesonide suspension which could not reduce the colitis parameters significantly.